Chapter 2.1.2 & 2.2.1 (Exam 1) Atomic Structure and Bonds Flashcards
An Element’s Atomic Structure Determines Its Properties
What determines how an atom will combine with other atoms?
of electrons
The # of electrons
What is an orbital?
The region where an electron is found at least 90% of the time
How many electrons can an orbital hold?
2
How are orbitals filled?
In a specific sequence of electron shells/ energy levels
How many electrons and orbitals do the first and second shell have?
First shell (innermost): 1 s-orbital; holds 2 electrons
Second shell: 4 orbitals (1 s-orbital and 3 p-orbitals); holds 8 electrons
How does the distance of the shell from the nucleus relate to the energy of the electrons within the shell?
The farther an electron shell is from the nucleus the higher the energy level of the electrons within the shell
Which electron shell determines how the atom behaves?
The outermost shell, or valence shell
What happens if the outermost shell is full? If it’s not full?
The atom is stable if the valence shell is full
If it is not full, the atom is more reactive/unstable
What do reactive atoms do to become stable?
Share, lose, or gain electrons resulting in atoms bonding to form molecules
What is the octet rule?
Tendency of atoms to form stable molecules resulting in full valence shells with 8 electrons
What is a chemical bond?
Attractive force that links atoms together to form molecules
Name some chemical bonds and interactions.
Covalent bonds
Ionic Bonds
Hydrogen bonds
Hydrophobic interactions
van der Waals forces
What is a covalent bond?
Atoms share one or more pairs of electrons so that the outer shells are filled
Each atom contributes one member of each electron pair
What is a compound?
pure substance made up of two or more different elements bonded together in a fixed ratio
What is the molecular weight of a compound?
sum of atomic weights of all atoms in the molecule
